142. Zero Indices and Powers of Powers
Learning Intentions
- To understand the meaning of an expression like
- simplify expressions in which the index is zero
- simplify expressions involving powers of powers
- expand expressions where a product is taken to a power, e.g.
Learning Intentions
- To understand the meaning of an expression like
- simplify expressions in which the index is zero
- simplify expressions involving powers of powers
- expand expressions where a product is taken to a power, e.g.
Pre-requisite Summary
- Know that an index tells how many times a base is multiplied by itself
- Be able to write powers such as
in expanded form - Know the index laws for multiplying and dividing terms with the same base
- Understand that a variable with no written index has index
- Be able to identify factors inside brackets
- Know that repeated multiplication can be written more efficiently using powers
- Understand that brackets group expressions together
- Be able to simplify simple algebraic products such as
Worked Examples
Worked Example 1
Write each expression in expanded form, then simplify:
a)
b)
c)
Worked Example 2
Simplify each expression with a zero index:
a)
b)
c)
Worked Example 3
Simplify each power of a power:
a)
b)
c)
Worked Example 4
Expand each product taken to a power:
a)
b)
c)
Worked Example 5
Expand and simplify:
a)
b)
c)
Worked Example 6
Simplify each expression:
a)
b)
c)
Problems
Problem 1
Write each expression in expanded form, then simplify:
a)
b)
c)
Problem 2
Simplify each expression with a zero index:
a)
b)
c)
Problem 3
Simplify each power of a power:
a)
b)
c)
Problem 4
Expand each product taken to a power:
a)
b)
c)
Problem 5
Expand and simplify:
a)
b)
c)
Problem 6
Simplify each expression:
a)
b)
c)
Problems
Understanding and Fluency
-
Write each expression in expanded form:
a)
b)
c) -
Simplify each power of a power:
a)
b)
c)
d) -
Simplify each expression with a zero index:
a)
b)
c)
d) -
Simplify each expression:
a)
b)
c)
d) -
Expand each product taken to a power:
a)
b)
c)
d) -
Expand and simplify each expression:
a)
b)
c)
d) -
Simplify each expression:
a)
b)
c)
d) -
Simplify each expression:
a)
b)
c)
d)
Reasoning
-
Explain why
means . -
A student says that
. Explain the mistake. -
Noah says that
because . Is he correct? Explain. -
Explain why
. -
A student expands
as . Describe the error.
Problem-solving
-
A pattern rule includes
. Write this in simplest form. -
A model for area uses
. Expand and simplify the expression. -
A science formula contains
. Simplify the result. -
A computer process gives
. Simplify the output. -
A student writes a term as
. Simplify the term. -
A design uses
tiles in one section. Expand and simplify this expression.
Potential Misunderstandings
- Students may think
means instead of multiplying the indices - Students may think a zero index gives the value
instead of - Students may forget that the zero index rule applies only when the base is not zero
- Students may confuse a power of a power with multiplying terms that have the same base
- Students may add indices instead of multiplying them in expressions like
- Students may think
means rather than - Students may forget to apply the power to the numerical coefficient as well, for example in
- Students may simplify
as instead of - Students may not use brackets carefully and lose track of what the power applies to